Motivational control of sexual behavior in Aplysia fasciata: sequencing and modulation by sexual deprivation and by addition of partners.

Variables similar to those affecting feeding behavior also modulate sexual behavior in Aplysia fasciata, indicating that mating is under motivational control. Motivated behaviors are often patterned into appetitive and consummatory components. Courtship, the appetitive phase of male sexual behavior, was temporally related to subsequent mating. Although many bouts of courtship failed to lead to mating, most incidents of mating were preceded by courtship. Motivation is also characterized by satiation after the goal of the behavior is achieved. We found an increase in likelihood to mate following a period of sexual isolation. Motivated behaviors are also modulated by environmental stimuli that induce arousal. Time spent mating was found to be a function of the number of potential mates accessible for mating. Number of A. fascinata participating in a mating group was also found to be a function of number of potential mates available.